Bending machine



Feb. 10, 1931.

R. L. HIBBAYRD smamue moms;

INVENTOR R. L. HIBBARD BENDING IACHINE Feb. 10, 1931.

Filed Nov. 4 Sheets-Sheet 2 CEKJW Feb. 10, 1931. R. L. HIBBARD BENDING near-us Filed 'Nov. 22, 1929 4 Sheets-Sheet 3 ITI INVENTOR 68 :g. .JW

/e? 6 MLL Patented Feb; 1:0, 1931 ROBEBTVL. n'IBB R-mon BELLEVUE, PEnNsYL VANIA BENDING MACHINE Application filed November 22, 1929, Serial no. 408,987?

The invention relates to'machines for "bending bars'or rods'into zig-zag form's primarily for use in making light trusses for floors and other structures. It has for its principal .5 objects the provision ofa machine of simple construction in whichthe labor required to operate is reducedt'o a minimum-in proportion to the output of the machmeywh-ich will form the bends in the bars with uniform- I ity and accuracy; and which will operate to make two bends in the stock at one timewith no more manipulation or labor on-the part of the operator in makingthe double bend than is reqiured n'makinga s ngle bend on '1 the ordinary bending machine." One embodiment of the invention isillustrated'in the accompany ng drawings, wherem:

with-certain of the parts lying above the 0. dies removed to-show'the parts beneath more clearly; Fig, 2 is a similar view with the bending dies in their other extreme of'move ment. Figs; 3 and 4: are elevations at opposite sides of the machine. Fig. 5 is a detail plan view of a part of the machine with the attachment applied for giving afsharp bend at the movable die, And Sis an end elevation of the parts, as shown in Fig. 5; jReferr'ing to'the' drawings," 1. is the base of the machine in which are mounted the vertical piyotrods 2 and 3, on which arejpivote d thelinks 4; and 5; Pivotally connected'to the ends of the. links byjthe pins 6 and 7 is the plate -8 which carries the movable die.

movementqin a' horizontal direction, is

mounted for arelatively -small amount 1 of vertical movement iniorde'rto free; it from the bent barafter the bending operation, as

,-later describedL This is provided for by This ,die consists of the members 9 and lO with the 1 Lying so that its slot 14 isin alignment mounting the die on the under side of a ribbed plate 18 pivoted upon the pin 19 sup- 1 ported in the lugs 20 projecting fromthe frame]. (Figs. 2 and 3)-.- The platelS is provided with'a depending arm 21, which 3 carries .a' second'arm 22 pivotedthereto atf The arnr 22' is clamped "yieldingly against th arm 21 by means of a spring 24 surrounding the bolt 25 secured'at its inner" end to thearm'21; -The arm 22 is provide'd at its end witha pin 26 engagingia cam27 carried by the shaft 28; The 'rotation ofthe cam oscillates the-arms 21- and 22 at timed 1 intervals, thus raising the' plate 18 and the 1 fixed die at proper intervals? The-use of I tl e arm 22 andspring 24 gives "a yielding 7 operation for preventing breakage in case Figure 1 1s a. plan view of the machlnef the movementof the plate 18 is positively 1interferedjwith, as sometimes occurs, when i the bar whichis being bent 1s vnot gott'en out r of the we. when the plate is moved down- :ward. The shaft 28sis driven froni'an elec tr c'motor 29 through'the intermediary of the motor shaft 30, the bevel gears 31 and 32, cross sha'ft33, worm Ed on theshaft33, worm' wheel? on the vertical shaft 3,6,bevel gears l i crank 42' and connecting rod 43. The 1 right back and. anthe the vertical shaft 7 36 bymeans [of the hand end of the rod 43 i's connected to the shoulder 44 (integral with the-link 4:) i I means of the short link 45, such linlcbeing pivoted to the shoulderby means of the pm 46 and to the connecting rod by means of the pi'n47. During the actuation of the link 4':

from the rod 4:3, the link'lt" oscillates back and forth; at one'timeoccupying theposition shown in engagement with the stop-pin 48; and at'another time occupyinga'position at approximately. degrees from the position shown in engagement with the stop vpin 491(Fig, This provides for a pause inthemovement of the. link 4 when it reaches two extremes of. oscillation wand gives time for 1 the operator-to shift thestock being'bent to a new position, v This period of delay at ex treme: positions is furtherfincreasedbythe.

vided with a gear 55 meshin witha driv-' ing pinion 56. The shaft 57 or the pinion 56 is driven from the pinions 58 and 59 and the gear 59 is provided with a sprocket 6O driven from the sprocket 61 by means ofla chain'62.

. The sprocket 61 is mounted upon the end of the shaft 33 whose drive has already been described. V 7

In starting the bending operation, the parts ofthe machine occupy the position shown in Fig. '1 with the slot 11 of the movable die in alignment with the slot 14: of the fixed die, and the endof the bar 12 is pushed through the slots until its end engages, the stop block 63 (Fig. 1 The machine is'then started, and the crank 42 moves the plate 8 carrying'the movable die 9,10 to the-position shown in Fig. 2, thus givin the bar two bends, oneof which is around the toe 17 of the fixed [die and the other of which is around the toe 13 of the movable die. Durg ing this movement the slotll is kept parallel to the slot 14:, due to the mounting of the plate/8 which'carriesthe movable die, upon th parallel links 4 and5. When this bend ing movement is completed, thecam27 swings the arms 22 and 21 to lift the plate 18 which carries the fixed die upward a slight distance. This movement serves to free the I fixed die from'the bar, so that this bar, now

partially bent, can be -moved back by the movable die to the start ng position of 1, preliminary'to pnshingthe bar ahead until its last benden 'a es the stoo 63; When the b bar 18 back again at tne position of .dlg. 1,

the cam 27has rotatedjfar enough to permit the plate and fixed die to move down so that the slot 14 fits over the bar. The rotation of :the: rolls 52 and 53 helpto carry the bar 7 v ahead when'it is released bythe dies. While the bar is held against movement by the dies,

the rolls "slip over tl1ebar,.which they en gage with only a slight amount ofpressure. It w ll be observed that each movement of the dies produces two bends in the stock'a'nd that this is. due to the fact that the movable die is moved'so that its slot is maintained throughout its movement in-parallehsm with the slot'of the fixed die. This double bending has thefurther advantage that it does not cause thefbar to swing back and forth on wide are as is the case-.wherethe machine employed formscnly a's'ingle bendeat each; operation, which are increases as the length of bent stock increases. V

The bending apparatus, asy'above" scribed i will "not make a sharp [bend around blocked in bending around the toe 17 of the the toes 13 and'17, unlessspecial provision is made to accomplish this result. This is easily accomplished with respect to the bend at 17 but involves more difiiculty in bending sharply about the toe 18. To accomplish the result at the toe 17, a block 64 isprovided upon the link 1 whichengages the bar 12 on the side opposite to the toe 17 This block moves around with the link forcing the bar to bend sharply around the toe, and occupying the position shown in Fig. 2 at the end of the bending movement. To accomplish the v desired result at the toe 13,.the attachment shown inFigs. 5 and 6 is employed. This device is omitted from the other figures of the drawings in orderto avoidconfusion, but its location with; respect to the body of the machine will -beclear from inspection of such Figs. 5 and 6, which shows the move able dies and associated parts of the machine, and upon comparison with Fig; 4, which shows the plate and post carried by the'movable die upon which the device is supported. a T

, Secured upon the die member 10 bvthe three rivets 65 Fig. 5) ,is aplate 66, which in turn carries a post 67' in vertical'alignment with the Spin 6. 'Slidably and rotatably mounted.onthepost' is the block 68. This blocl'r has depending finger 69,-which lies against the bar12 on the side thereof opposite to the bending toe 13 of the die and performs I the, same function in bending aroundrthis toe asisj accomplishedby.the

fixed die. The block 68 iscaused to rotate about the post 67 in 'a'counter clockwise d1; rection asthe-movable die moves from the fullline positionof Figs. 1 and 5 to that of 2 and to thedotted line position of Fig. 5 by a radiusarm'69F mounted in a slot 70 through the top, of the block and held by a plate il. "The other endof the-arm (39,is

pivoted upon abolt la carried by a bracket 72 securedto: the plate 18; which carries the 1 fixed die. In moving from thefull line positionrof' Fig. 5 to thedottedline position of such, figure. the 'fing'erbt) is kept against the bar :12, forcing around the toe 13. 1 n V After the bar has been-bent to the dotted line position of Fig. 5) it is necessary to move the finger 69 upward to releasethe bar 12 preliminary to moving the die'back'to start ing position, and this is accomplished by the lever 7 2 pivoted upon the pin 73, ancl.nor-

mally held in the horizontal position shown by the spring 74.. \Vhen the parts have been moved to the :dotted line position of Fig. 5 the end of the lever lies abovetheplate 18, s am: when this plate is ,mov'ed vertically torelease the fixed'diefrom the b'ar'as here- 'tofo're explained, thelever is also lifted, slide ing the block 68 upward on-?tlie, -pin;67 and 1 moving the'finger upward to release position [itkto bend sharply 1e bar 12; The block 68 "with its finger'r69 is :held in tiis elevated positicnward so that. it moves of? oif the shoulder.

. movement bet iveentheipinand the latch plate is such as to cause the parts 'tc as The release of the latch plate from the shoulder to permit-the'block 68 to move back to the position of F ig. 6, occurswhen the parts return to the full line position of Fig; 5'. The movement of the latch plate at this time: is accomplished by a pin- 79 extending through the po'st'just above theshoulder '28.

In moving from the dotted line position of Fig. 5 to the full l ne position, the relative sumeithe relation shown in full linesfa-t which time the pi'nzpushes the'latch plate on the shoulder 78, allowing th'eblo'clr" 68 to drop down by gravity to the positionshcwn in Figfifi. f 7 7 7 The operation of. the mac hine" will be apparent fromthe; foregoing description. With the parts'in the position shown in Fig. 1', the bar or stock 12 to "Debent, is pushed up through the die slots '11 and 14 till its end engages thestop 68. The drivec'f the motor 29 operating through gearing describ'ed and the Cra-nlr iQ, then swings H the plate Sand movable "die 9, lO'carried by the parallel links a and 5 upto the position of Pi 2, thus bendin the bar around thetoes 17 and 13 ofthe two dies. The cam 2-7 operating through the arms "22 and '21 no N swings the ribbed plate 18 carr ing the fixed die upward to" release it from the bent bar,

andatthe same time, the depending 69 carried bythe block 68 is niovedu'pward by the lever 72, whose end lies above the plate 18. This releases the'fbar 12 from the preliminary to movingthe movahle die I associated partsib'ac k tou e position oi' 9F 5. 1, and such finger ;:(and the block '68 which carriesit) 'areheld'u'p in this positio'n by the latch platuntil the parts: reach the posi tion of Fig; 5'when'the'platei's released from the shoulde'rfZS by the pin 79] The sea stantl'y rota-ting roll's 52 and 53fieed the 12 forward when 1t'1s reieascd from the dies,

7 asiaboi-e'describe-d. ld ith themachine parts again in the position of'Fig; 1, the operator again positions theibar 12 in the die slots 11'- vand le'cwith the rearmost bend loft-the stock against the stop 63' (Fig. '11) and the-parts are again operated to giveithe bar another 7 double bench. This operation is" continued untilthe entire bar is bent.

It Will'fbe amderstood; that the term slot as and means whereby. the die is caused to employedin the specification and claims in connection with the dies is used in its broad sense as meaning any means. for engaging the bar on its two sides'and holding it duringthe bending operation. Further, while two dies each having a'slot is the preferred construction, it is not absolutely necessary the slots insures a sharper bend than can be secured if a die merely has a bend ng nose,

but in some cases sharp bendsare not Jrequired or any part of the "bends which arethat each the should have a slot; The use I not made sharplyvenough may be made more i a bending toe at the end thereoieone of-w'hich dies'is fixed, and-the .other mounted for swinging'movement about the fix'edzfdieasa center, means whereby the slot of the mo' v-' a'ble die is'maint ainedfin parallelism with that vof thefixed die durin the swin in b b C] movement of such movable die, power means for swinging the movable die backand'forth,

V pause when in its'itwo' extreme positionsl 2! In combination in a bar bending mas cli ine, two dies in alignment for receiving theb'arito be bent and each havingaslot with "a bending toe fat the end thereof, one of which dles 1s fixed, and the other mounted for swinging movement about-the fixed die as a center, means wherebyv the slot. of the motable die is maintained'in parallelism with that of theafiXed die durin the'swin in move- :inent o'f-such movable die, a power-driven crank for swinging the movable die back and forth, and lost motion connections. intermediate the crank and die for causing the die to pause in its two extreme positions 3. In combination in a. bar-bending m chine, two r dies in "alignment Efor receiving thebar to be bent and each ha 'ing'a isl'ot'wit-h' abending toe at the end thereorfi onexoi which i l G dies is ifixedyand the other mountede'ifor I swinging movement abouttheffixed die a I center, means whereby the slot o'f'ithefmovable die s 'mainta ned ln parallelism with 1 that cf thefixed dieduring the swinging movement'of such movable die, power means for giving the movable jdi'e, its: swinging movement, and means for shifting the fixed die transversely of the plane cit-movement of the'zinovable die at the endfo-f thebending movement in order to release such fi'iied'die from the bar and permitthebar to be moved forward preliminary to another bending operation. v

' 4-, In combination a b'an bending chine; two dies? in alignment for receiving the loart'o be bent an'deach having a slotivith 1 a bendingtoe at the end'thereoi cne of which dies is fixed, andjthe other" mounted for' swinging movement about the fixed die as a center,means whereby the slot of the movable die is maintained in parallelism with that of the fixed dielduring the swinging Vmovement of'such movable die, power means for giving the movable die its swinging movement, a finger carried by the movable Stu die and arranged to engage said bar in advance of the toe of the die on the-side of the bar-opposite to such toe,and means for rotating the finger about the toe of said movable die during the swinging movement there- .of, causing the bar to make arelatively sharp bending toe at the end thereof, one of which 7 dies vis fixed, and the other mounted for swinging movement aboutthe fixed die as a center, means whereby the islot of the movable die is maintained in parallelism with that of'the fixed die during the swinging movement of such movable die, power means chine, two dies in alignment for receiving the for giving the movable die its swinging movement, a finger carried bythe movable die and arranged to engage said bar in advance of the toe of the die on the side of the bar opposite to such toe, and means for frotating the'finger about the toe of such movable die during the swinging movement thereof, causing thebar to make a relatively sharp bend around'such'to'e, said means comprising a radius arm pivoted atthe center about which the movable die swings.

'6. In'combination in a .bar bending machine, two dies in alignment for receiving the bar to-be bent andeach having a slot with a bending toe at the end thereof, one of which 'dies is fixed, and the other mounted for swinging movement about the fixed die asa center, means whereby the slot of the movable die is maintained in parallelism with that of the fixed die during'the swinging movement of such movable "die, power means for givingthe movable 'die its swinging move ment, a finger carried by the movable die and arranged to. engage. said bar in advance of the toe ofthe' die on the side ,ofthebar opposite to such toe, means for rotating thefin'ger about the toe of such movable die during the swinging movement thereof so as to cause the bar to make a relatively sharp bend around such toe, and means for lifting the finger to release the bar when the movable die reaches. its extreme bending position.

7.3111 combination in a bar bendingmabar to be bent and each having a slot with a bending toe at the end thereof, oneof which dies is fixed, and the other mounted. for

"swinging'movement about the fixed die as a center, means'whereby the slot of the movable die 'is maintained in parallelism with that zof'the fixed die during the swinging movement of such movable die, power means for giving the movable die its swinging movement, a finger carried byt-he movable die and arranged to engage said bar in advance of the toe of the die on the side of the bar opposite to such toe, means for rotating the finger about the toe of such movable die duringthe swinging movement thereof so as to cause the bar to make a relatively sharp bend around such toe, means for lifting the finger to release the bar when the movable die reaches the extreme bending position, and means operated by the movementof the mov able die back to starting position to cause ative position. 1

8; In combination in a bar bending machine, two dies in alignment for receiving the bar to be bent and each having a slot with a bending toe at the end thereof, one of which dies is fixed, and the other mounted for the return of the finger to engaging or o'per swinging movement about the fixed die as a center, means whereby the slot of the movable die is maintained. in parallelism with that of the fixed die during the swinging. movement'of such movable die, power means for giving the movable die its swinging movement, means for shifting the fixed die laterally at the end of the bending movement to releasethe bar from such fixed die, afinger carried by the movable die and arranged to engage said bar in advance of the toe of the die on the'sideof the bar opposite to such toe, means for rotating the finger about. the toe of such movable die'during theswinging movement thereof so as to cause the bar to make'a relatively sharp bend around theftoe, i

and means actuated by the lateral movement of the fixed die for lifting the finger to release the bar when the movable die reaches its extreme bending position.

9. Inacombination in a bar bending machine, two dies in alignment for receiving the bar to be bent and eachhaving a slot with a bending toe at the end thereof, one of which dies bis fixed, and the other mounted for swinging movement about theffixed die as a center, means wherebythe slot of the movable die is maintained in,parallelism vwith that of the'fixed die during theswinging movement ofsuch movable die, power means for giving the movable die its swinging movement, means for shifting thefixed die-laterally at, the end of the bending movement to release the-bar from such fixed die,a:finger carried by the movable die and arranged to- 1 treme bending position, and means operated by the movement of the movable dieback to starting position for releasing the finger so that it returns to its operative starting position.

In testimony whereof, I have herennto subscribed my name this 21st day of November,

RoBEnrn HIBBARD. 

